Process of cracking hydrocarbon gases and enriching with liquid hydrocarbons



Dec. 12, 1933. J. A. PERRY PROCESS OF CRACKING HYDROCARBON GASES ANDENRICHING WITH LIQUID HYDROCARBONS Filed Dec. 19. 1929 Patented Dec. 12,1933 1,939,410 -rnociiss or CRACKING HYDROCARBON GASES AND ENRICHINGHxpRooARBoNs WITH LIQUID Joseph A. Perry, Swarthmore, Pa., assignor toThe United ,Gas Improvement Company, Philadelphia, Pa., a corporation ofPennsylvania Application, December .19, 1929 Serial No. 415,162..

8 Claims. "(01. 196-1) The present invention relates to the productionof hydrocarbon gas and water-gas, by cracking hydrocarbon gas in anignited fuel bed, depositing excess carbon released by cracking withinthe a fuel bed, and utilizing the excess carbon together with otherfuel, byair blasting to store sumcient heat in the fuel bed,to-providefor the cracking of further hydrocarbon gas and theutilization of the remaining-excesscarbon in the production'of #101water gas, by steaming the fuel bed.

More particularly the present invention relates to the crackingin thefuel bed of hydrocarbon gases produced extraneous to the apparatus, as

for instance; by-product refinery oil gas or natural gas. i

I- havefound in the cracking of such gas that the production isbestcarried on from astan'dpoint of ease of operation and. thermalefficiency,

if the fuel bed conditionaquantities of hydrocar- 201 bongas, air andsteam, and cycle arrangementv are such, that the reformed hydrocarbongastogether with thewater gas, form a mixed gas having a-caloriflc powerofbetween 400 and 500 B. t. u. per-cubic foot,-preferably about 460 B.t. u. per cubic foot. .-Such a mixed gas requires enrichment to bring itup to the standards of calorific power at present in force in mostcommunities for distribution for domestic and industrial consumption.

It has been proposed to enrich such gas by adding to it a portion of theinitial uncracked hydrocarbon gas, orlightly cracking a portion of theinitial hydrocarbon-gas and adding the lightly cracked-gas to the watergas and hydrocarbon gas all. produced in the fuel bed. l I-havefoundth'atthere are objections to th above procedures and have discovered animproved method of operation. In the'operation ofcrackin'gthe'hydrocarbon gas. in the fuel bed, an

M0. appreciable amount of stiil' pitch is produced and little fluid tar.A portion of this pitch is carried out of the fuel bed and deposits inaccessory apparatus employed for cooling, purifying and transporting thegas, as for instance, the wash 5. boxes, condensera'drips, etc. Thispitch is very stiff or viscous and is difllcult of removal. 7 When theinitial uncracked hydrocarbon gas is used for enrichment, or when theinitial hydro carbon gas is lightly crackedand used for enrichment thisdifiiculty'-exists,-'-the character ofthe pitchis not changed. Theinitial hydrocarbon gas imparts no fluidity to the pitch, and the lightcracking of the initial hydrocarbon gas does not produce'sufilcientfluid tar to render the pitch fluid. i v

I have foundthat if'I- store the heat of the air blast gases from thefuel bed and utilize the heat, for the vaporization of liquidhydrocarbons-such as, for instance, gas oil, and the subsequent fixingof the'vapors, th'e quantity of oil required for enl richment willproduce sufficient fluid tar-that when mixed withthe stiff pitchproduced by the cracking operations in the fuel bed, renders themixture'sufiiciently- 'fluid to be pumped without difficulty.

The invention will be further described in-connection with the attacheddrawingwhich forms apart of this specification, which shows in partialside elevationand partial verticalcross section, apparatus by means ofwhich the invention may be performed. V

Referring. to the drawing,

1, 2, 3- and 4 are vessels similar to the water gas generator,carburetter, superheater and wash box, respectively, of a carburettedwater gas set, .andfor convenience will be referred to as such.

9 The water gas generator 1 is provided with the ignited fuel bed 5 ofcoke, coal or like material.

It is also provided with air-blast supply means 6, for air blasting thefuel bed, steam supply means '7 and steam supply means 8,-for-up and fordown steamingthe fuel bed. The generator is alsoprovided with thehydrocarbon gas supply means 9 and 10 for passing hydrocarbon gas up ordown through the fuel bed.

1 The generator is'connected with the carburet- 'ter 2, by connection'llprovided with valve 12 and leading from above the fuel bed, and byconnect'ion 13 provided with valve 14, leading from below the fuel bed.15 is a supply of secondary air to the carburetter. a

The carburetter is provided with the heat. storage'material 16 such ascheckerbricks or other refractory substance and with the oil spray 17.The carburetter is connected to the superheater' 3 by -the connection18.

The superheater is provided with the heatv storage material 19, a suchas checkerbricks 'or other refractory substance, with the stack valve 20and with the connection 21 leadingto the wash box 4. 22 is the offtakefrom the wash box leading through valve 23 to-condenser 24.

- The wash box is provided with. theliquid inlet supply means generallyindicated as 25, and with the liquid outlet 26 leading toseal pot 27. 28

is the liquid outlet of the seal pot 27.

The condenser 24 is provided with the gas outlet 29 leading tothe'relief holder (not shown) and is also provided with the coolingliquid inlet 11.0

30 and the liquid outlet 31 leading to seal pot 32. 33 is the liquidoutlet from the seal'pot.

There are numerous variations of operating cycles in which the presentinvention may be employed, and from which the following are chosen forillustration.

With valve 14 closed and valves 12 and 20 open, the fuel bed is blastedwith air supplied at 6. The resultant blast gases pass through'thecarburetter 2 and the superheater 3, wherein they are burned with airsupplied at 15, storing their heat in vessels 2 and 3. The burned gasespass through valve 20 to atmosphere.

The air blast is terminated, and with valves 14 and 20 closed and valves12 and 23 open, steam is admitted to the fuel bed through 7, theresultant water gas passes through the carburetter and.

superheater to the wash box. Simultaneously oil is admitted to thecarburetter, vaporized therein, and the resultant oil vapors fixed inthe carburetter and superheater. The carburetted water gas passesthrough the wash box and condenser to a place of storage (not shown). Inits passage through the wash box and condenser, tar is condensed out ofthe gas. Further tar condenses out in therelief holder.

After the above water gas run, hydrocarbon gas is introduced to the fuelbed alternately at 9 and 10, and passed alternately up and down throughthe fuel bed, and cracked therein to reformed gas which passes to thecarburetter and superheater, valves 12 and 14 being appropriatelyoperated. The reformed gas passes from the superheater through the washbox and condenser to storage. During its passage through the wash boxand condenser, tarry products (largely pitch) are condensed out of thereformedgas. These mix with the fluid tar condensed out of the fixed oilgas, producing a mixture sufficiently fluid to be readily handled.Further pitch is condensed in the relief holder, tar extractor andpipes, but this also mixes with fluid tar and oil condensed out of thecarburetted gas, producing readily handled material. I

The excess carbon released by the cracking of the hydrocarbon gases inthe fuel bed, remains there for subsequent utilization in air blastingto store heat for the cracking of further hydrocarbon gas, and for theconsumption of the remaining excess carbon in the production of watergas.

After a short uprun purgewith steam supplied at 7 the above cycle may berepeated.

Downruns with steam supplied at 8 may be made as desired to balance thefuel bed conditions, and the resultant water gas may be carburetted inthe carburetter and superheater with oil supplied at 17. a V

. As an alternative, the reformed hydrocarbon gas may be carburetted inits passage through the carburetter and superheater.

Another alternative method of operation is as follows: 7 V

Blast the fuel bed with air supplied at 6, burning the resultantblastgases in the carburetter and superheater, to store their heat, withsecondary air supplied at 15.

Simultaneously pass steam and hydrocarbon gases alternately up and downthrough the fuel bed, to produce mixed'water gas and reformed gas,passing the mixed water gas and reformed gas through the carburetter andsuperheater and carburetting them with oil supplied at 17.

Following an uprun steam. purge, this cycle may be repeated.

I claim:

1. A process for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid including the following steps: passing hydrocarbongas through an incandescent fuel bed, cracking the gas therein toreformed gas with a consequent deposition of carbon in the fuel bed andthe production of stiff pitch; passing steam through the incandescentfuel bed, generating blue water gas, utilizing carbon equivalent inamount to a portion of the deposited carbon, carburetting the .bluewater gas, utilizing the stored heat for the carburetting and for fixingthe carburetted water gas, and producing fluid tar; mixing the stiffpitch and the fluid tar so that the consequent mixture may be morereadily removed from the gas making apparatus; and air blasting the fuelbed storing heat therein and utilizing fuel equivalent in amount to theremaining portion of the deposited carbon.

2. A process for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid including the following steps: passing hydrocarbongas through an ignited fuel bed thereby producing reformed gas, andcondensing stiff pitch from the reformed gas; another step being,carburetting gas with oil thereby producing carburetted gas, andcondensing fluid tar from the carburetted gas in the same vessel withthe stiff pitch, thereby mixing the stiff pitch and the fluid tar so.that the mixture can be readily handled.

3. A process for the manufacture of combustible hydrocarbon gasandhydrocarbon liquid including the following steps: air blasting anignited fuel bed to incandescence; another step being, making a run withsteam through the fuel bed and carburetting the resulting blue water gaswith oil, thereby producing fluid tar, and condensing the fluid tar outof the carburetted water gas; another step being, passing hydrocarbongas through the fuel bed, thereby producing reformed gas and stiffpitch, and condensing the stiff pitch out of the, same gas in the samevessel with the fluid tar, thereby mixing the stiff pitch and the fluidtar so that the mixture can be readily handled; and another step being,making an uprun purge with steam.

4. A process for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid including the following-steps: air blasting anignited fuel bed; another step being, makingan uprun with steam throughfuel bed, carburetting the blue water gas so produced with oil, andcondensing fluid tar out of the carburetted water gas; another stepbeing, passing hydrocarbon gas through the fuel,bedproducing reformedgas and stiff pitch, condensing stiff pitch out of the reformed gas inthe same vessel with the fluid tar, thereby mixing the stiff pitch andthe fluid tar so that the mixture can be readily handled; and anotherstep .being, making a backrun'with steam down through the fuel bed andcarburetting the blue water gas so produced with oil.

-5. A process for the manufacture of combustible, hydrocarbon gas andhydrocarbon liquid including the following steps; air blasting anignited fuel bed; another step being, making a run with steam throughthe fuel bed and carburetting the blue water gas so produced with oil,and condensing fluid tar out of the carburetted gas; another step being,passing hydrocarbon gas through the fuel bed, producing reformed gas andstiff pitch, carburetting the reformed gas with oil, condensing thestiff pitch out of the reformed gas in the same vessel with the fluidtar, thereby mixing the fluid tar and the stiff pitch so that themixture can be readily handled; and another step being, making an uprunpurge with steam.

6. A process for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid including the following steps: air blasting anignited fuel bed; and another step being, simultaneously passing steamand hydrocarbon gas through the fuel bed, thereby producing blue watergas and hydrocarbon gas and stiff pitch, carburetting the resulting gaswith oil, and condensing the stiff pitch and the fluid tar resultingfrom the carburetting oil in the same vessel so that there results amixture of stiff pitch and fluid tar which can be readily handled. 7. Aprocess for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid including the following steps: air blasting anignited fuel bed; and another step being, simultaneously passing steamand hydrocarbon gas through the fuel bed, producing a mixed gas having acalorific power of from 400 to 500 B. t. u.-

per cubic foot, carburetting the mixed gas with oil, and condensing inthe same vessel the stiff pitch from the hydrocarbon gas and the fluidtar from the carburetting oil so that a mixture of stiff pitch and fluidtar which can be readily handled results.

' 8. A process for the manufacture of combustible hydrocarbon gas andhydrocarbon liquid, which process includes the following steps: passinghydrocarbon gas through an incandescent fuel bed producing reformed gasand stiff pitch and depositing carbon in the fuel bed, and condensingthe stiff pitch out of the reformed oil gas; another step being, airblasting said fuel bed consuming fuel and deposited carbon and producingblast gases, burning said blast gases with secondary air, and storingthe heat resulting from said combustion; and another step being, passingsteam through said fuel bed thereby generating blue water gas,carburetting said blue water gas withoil by means of said stored heat,and condensing fluid tar out of the carburetted water gas in the samevessel with said stiff pitch, thereby mixing the stiff pitch and thefluid tar so that the mixture can be more readily handled.

JOSEPH A. PERRY.

